Wait list death and survival benefit of kidney transplantation among nonrenal transplant recipients

The disparity between the number of patients waiting for kidney transplantation and the limited supply of kidney allografts has renewed interest in the benefit from kidney transplantation experienced by different groups. This study evaluated kidney transplant survival benefit in prior nonrenal transplant recipients (kidney after liver, KALi; lung, KALu; heart, KAH) compared to primary isolated (KA1) or repeat isolated kidney (KA2) transplant. Multivariable Cox regression models were fit using UNOS data for patients wait listed and transplanted from 1995 to 2008. Compared to KA1, the risk of death on the wait list was lower for KA2 (p < 0.001;HR = 0.84;CI = 0.81-0.88), but substantially higher for KALu (p < 0.001; HR = 3.80;CI = 3.08-4.69), KAH (p < 0.001; HR = 1.92; CI = 1.66-2.22), and KALi (p < 0.001; HR = 2.69; CI = 2.46-2.95). Following kidney transplant, patient survival was greatest for KA1, similar among KA2, KALi, KAH, and inferior for KALu. Compared to the entire wait list, renal transplantation was associated with a survival benefit among all groups except KALu (p = 0.017; HR = 1.61; CI = 1.09-2.38), where posttransplant survival was inferior to the wait list population. Recipients of KA1 kidney transplantation have the greatest posttransplant survival and compared to the overall kidney wait list, the greatest survival benefit.